(1) Field of the Invention
The present invention relates to a pen type recording device for forming characters, figures, graphs and the like on a sheet fed by a platen. Particularly, it is concerned with a sheet pressing mechanism capable of holding edge portions of a sheet positively on the platen.
(2) Description of the Prior Art
Various conventional recording devices such as impact printers have been proposed, but it has been impossible to draw figures, graphs and the like freely with such printers, although such printers can form characters and other symbols. In an effort to eliminate such inconvenience, a pen type recording device has recently been put to practical use, in which a recording sheet is held around a roller serving as a platen so as to be fed in the circumferential direction of the platen, and a pen opposed to the sheet can be moved in the axial direction of the platen. By controlling the feed of the sheet and the movement of the pen, it is possible to form on the sheet not only characters, but also figures and the like. For forming a figure or a graph on a recording sheet by such pen type recording device it is sometimes necessary that the recording sheet be reciprocated many times by the platen. At this time, slippage may occur between the platen and the sheet, thus causing deviation of the feed of the sheet from the motion of the platen, which may result in a distorted figure being formed on the sheet. Therefore, it is necessary that the sheet be held positively with respect to the platen.